The present invention relates to temperature-producing conductive-resistive coating and medium, and to a method of producing a variety of articles therefrom.
There have been many attempts to produce electrically-conductive coatings such as paints. Generally, there are two types of electrically-conductive coatings. The first is a low resistivity, high conductivity paint that contains a pigmentation of metal particles while the second is a high resistivity, low conductivity paint that is formed from compositions containing carbon or graphite that oxidize at temperatures above 600.degree. F., and lose their electrically conductive ability.
Low resistivity paints have traditionally been used to provide coatings having high conductivity for connecting conductors that require a superior electrical bond with a minimum resistance. Generally, low resistivity paints cannot be applied to materials in order to produce temperature adjustable heating elements because the low resistivity paint requires a high volume of current to generate a reasonable output of heat. In contrast, the resistivity of traditional highly resistive paints is often so high that a relatively high voltage drop is required in order to generate sufficient heat. Also, the use of traditional high resistivity paints within highly elevated temperatures oxidize and lose electrical conductivity permanently. Furthermore, when either of the above-identified traditional conductive paints are applied to various substrates, cracks and flaking of the paint often develop over a period of time. Cracks and flaking of the paint coating may cause arcing and unequal power distribution sacrificing safety. Concomitantly, a breakdown in the temperature adjustable property of the coating may occur thereby causing an unequal heat distribution upon the surface of the article.
It is therefore an object of this invention to provide an electrically resistant temperature-adjustable conductive composition for application to a variety of substrates that can be formed into various shapes with structural integrity without a substrate to provide temperature control properties in a high temperature range without the non-continuous electrically conductive components oxidizing and losing conductivity in an oxygen atmosphere in temperatures above 600.degree. F.
It is another object of the invention to provide an electrically resistant temperature-adjustable conductive composition for application to a variety of materials wherein a thin coat of the electrically-resistant temperature-adjustable conductive composition does not inhibit the inherent flexibility of a flexible substrate to which the composition is applied therefore maintaining the structural integrity of the substrate.
It is still another object of the invention to provide an electrically resistant-temperature-adjustable conductive composition which bonds well and is capable of maintaining its integrity at high temperature ranges as a coating or as a structural material.
Other and further objects will be made known to the artisan as a result of the present disclosure and it is intended to include all such objects which are realized as a result of the disclosed invention.